1o2image(8)                    OCFS2 Manual Pages                    o2image(8)
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NAME

6       o2image - Copy or restore OCFS2 file system meta-data
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SYNOPSIS

9       o2image [-r] [-I] device image-file
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DESCRIPTION

12       o2image  copies  the OCFS2 file system meta-data from the device to the
13       specified image-file. This image file contains the file system skeleton
14       that  includes  the inodes, directory names and file names. It does not
15       include any file data.
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17       This image file can be useful to debug certain problems  that  are  not
18       reproducible  otherwise.   Like  on-disk  corruptions. It could also be
19       used to analyse the file system layout in an aging file system with  an
20       eye towards improving performance.
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22       As  the  image-file contains a copy of all the meta-data blocks, it can
23       be a large file.  By default, it is created  in  a  packed  format,  in
24       which  all  meta-data  blocks are written back-to-back. With the -r op‐
25       tion, the user could choose to have the file in  the  raw  (or  sparse)
26       format,  in which the blocks are written to the same offset as they are
27       on the device.
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29       debugfs.ocfs2 understands both formats.
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31       o2image also has the option, -I, to restore the meta-data from the  im‐
32       age  file  onto  the  device. This option will rarely be useful to end-
33       users and has been written specifically for developers and testers.
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OPTIONS

37       -r     Copies the meta-data to the image-file in the  raw  format.  Use
38              this  option only if the destination file system supports sparse
39              files. If unsure, do not use this option and let the tool create
40              the image-file in the packed format.
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43       -I     Restores meta-data from the image-file onto the device. CAUTION:
44              This option could corrupt the file system.
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47       -i     Interactive mode - before writing out the image file print  it's
48              size  and ask whether to proceed. This setting only applies when
49              '-I' is not specified. It can be useful  when  the  file  system
50              holding  the  image is low on disk space and the user might need
51              to free up space once the target image size is calculated.
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EXAMPLES

55       Copies metadata blocks from /dev/sda1 device to sda1.out file.
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57       # o2image /dev/sda1 sda1.out
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59       Copies meta-data blocks from sda1.out onto  the  /dev/sda1  device.  As
60       this command over-writes an existing volume, please use with CAUTION.
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62       # o2image -I /dev/sda1 sda1.out
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SEE ALSO

66       debugfs.ocfs2(8)   fsck.ocfs2(8)   fsck.ocfs2.checks(8)   mkfs.ocfs2(8)
67       mount.ocfs2(8) mounted.ocfs2(8) o2cluster(8) o2info(1) tunefs.ocfs2(8)
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AUTHORS

71       Oracle Corporation
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75       Copyright © 2007, 2012 Oracle. All rights reserved.
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79Version 1.8.7                    January 2012                       o2image(8)
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